A conventional fastener driving tool has a tendency that, with use of a fastener having small head and line diameters and a short length, when the fastener is driven within an injection passage, its inclination angle is increased to thereby increase the frequency of occurrence of fastener buckling.
To prevent such poor driving (bucking), conventionally, there is used a contact nose (see, for example, JP-A-2007-203419). The contact nose is a member to be connected to the leading end of a contact arm constituting a safety device of a fastener driving tool and, when the contact nose is pressed against the surface of a driven member, the contact arm is moved upward to put a drive mechanism into a drivable state. When the inside diameter of the contact nose is formed substantially equal to the inside diameter of a nose portion of the tool, the inclination of the fastener in driving can be prevented. Also, the contact nose is formed such that, in fastener driving, it is projected beyond the nose portion and is contacted with the driven member to thereby drive out the fastener from an injection port formed in its leading end. Therefore, even while the nose portion is floating due to reaction generated in the fastener driving, the adjustment of the fastener driving depth and the like, the contact of the contact nose with the driven member can be maintained, whereby the attitude of the fastener can be guided up to the completion of the driving operation. That is, even with use of the fastener having small head and line diameters and a short length, the contact nose can prevent the inclination of the fastener to thereby reduce the occurrence frequency of the fastener buckling.